philip@cel.cummins.com (Philip D. Pokorny) (05/29/91)
We had a real problem here that we solved with SCSI disks... About 80% of our network-wide diskspace was on three DSP90 nodes with four 440 Mbyte drives each. The DSP90's and the storage volumes were getting harder and more expensive to maintain... We just recently solved the problem by moving all the files from the DSP90's to three DN2500's with 20 Mbytes of main memory and two 1.2 Gbyte SCSI drives. The cost was considerably cheaper than purchasing a similar configuration of 400 series nodes. The 2500 we started with is just a bare-bones, minimally configured 2500. That means 14 inch display and 4Meg of memory installed and your choice of networking options. We upgraded the memory in the 2500's using standard PC SIMM memory of the 4Meg x 1 80ns variety which is widely available. You must purchase and install memory for the 2500 in sets of 4 SIMMs. Also, if you are mixing SIMM sizes, (ie 1Meg and 4Meg) the 4Meg must come first and the 1Meg last. Also if there is any 4Meg memory, there can only be 1 set of 1Meg memory. (This is because the physical memory must be contiguous.) We purchased our memory from DATARAM because we got a good corporate discount and because they would guarantee that the memory would work, but you should be able to use any PC compatible memory. (caveat emptor) The drives we purchased are made by HP and have a 5 YEAR warranty. Most other SCSI drives have only a 1 or 2 year warranty with optional extensions. You should check around in your area and your suppliers for the best price you feel comfortable with. We are currently using both the 660 Meg and 1.2 Gig drives from HP. They format to 637 Meg and 975 Meg respectively... Hope this helps... Sincerely, Philip D. Pokorny philip@cel.cummins.com PS. Those old DPS90's... Well now they are booted diskless to the 2500's so that we can still use the Multibus cards that were in them that support our SNA, 9-track tape, Versatec and Imagen peripherals... . :)